Search PubMed⌕ Search

Biomedical subjects

A Shah

Publications and source records attributed to A Shah.

At least 307 records · Page 17Linked to original sources
PubMed1992

Isolation of HIV-1 from plasma of infected individuals: an analysis of experimental conditions affecting successful virus propagation.

Experimental conditions affecting the successful propagation of HIV-1 from the plasma of seropositive individuals were examined. It was determined that whole blood samples collected with lithium heparin as the anticoagulant, immediate plasma separation, and immediate culturing were best suited for obtaining viable virus from plasma. Virus was isolated by infecting fresh phytohemagglutinin-stimulated normal donor peripheral blood mononuclear cells (PBMCs) with plasma followed by weekly cocultivation with new target cells. The plasma virus isolation rate was the greatest and HIV-1 titers were the highest for those individuals with less than 200 CD4+ cells/mm3 and decreased as the level of CD4+ cells approached normal values. We were able to obtain positive cultures from 29.5% of those patients with CD4+ counts greater than 500/mm3. HIV-1 titers in plasma also correlated with high serum p24 antigen levels when serum was treated with glycine to dissociate antigen-antibody complexes.

Adult↗
PubMed1992

Relationship between two measures of upper extremity strength: manual muscle test compared to hand-held myometry.

One hundred and twenty-two individuals with spinal cord injuries at levels C4-6, Frankel classifications A through D, were evaluated to determine the relationship between the manual muscle test (MMT) and hand-held myometry as accurate methods for measuring muscular strength. More specifically, this study attempted to define a range of myometry scores that could be correlated with discrete MMT grades. It also investigated which of the two modalities (MMT or hand-held myometry) is the best reflection of improvement in muscle strength over time. Sequential motor strength examinations using both modalities were performed at 72 hours, one week, and two weeks post SCI and then one, two, three, four, six, 12, 18, and 24 months post injury. The data analyses included calculations of Spearman ranked correlations, analyses of variance, and linear regressions. Results showed that 22 of 24 correlations between MMT and myometry were significant at p values less than .001. The range of myometry measurements for a particular MMT grade appears to be most specific for MMT scores less than 4 (ie, poor-plus to good), and less specific for MMT scores greater than or equal to 4. The results of this study also indicate that myometry measurements detect increases in strength over time, which are not reflected by changes in MMT scores.

Adolescent↗
PubMed1992

Modulan grip-aids for leprosy patients.

Made-to-measure Modulan grip-aids were fitted to 755 articles for 155 patients with hand deformities due to leprosy. The acceptance of the grip-aids was, in general, good. No instance of contact dermatitis or skin irritation was reported. These grip-aids facilitated a normal grip with crippled hands, and thus considerably improved the quality of the patient's personal and working life. They increased the patient's self-esteem and self-confidence because he/she could handle everyday objects or tools without the help of others and could do his/her job--an important step toward social and economic rehabilitation.

Epoxy Resins↗
PubMed1992

Hydatid bone disease of the pelvis. A report of two cases and review of the literature.

Hydatid disease is caused by a parasitic tapeworm Echinococcus. This parasite in larval stage can thrive in many parts of the body, most frequently in the liver. Hydatid disease in bone is rare, but in areas where hydatid disease is endemic, it must always be considered in the differential diagnosis. Two cases of hydatid bone disease of the pelvis are reported. The treatment of choice is a combination of chemotherapy and surgery.

Aged↗
PubMed1991

A specific and reliable bioassay for the detection of femtomolar levels of human and murine tumor necrosis factors.

A reliable, highly sensitive, cytolytic bioassay for the quantitation of both human and murine tumor necrosis factor (TNF) is described. The assay is 2-180-fold more sensitive than other currently described bio- or immunoassays (limits of detection: 500 fg/ml (29 fmol/l) human TNF-alpha, 200 fg/ml (12 fmol/l) murine TNF-alpha and 130 fg/ml (7 fmol/l) human TNF-beta). The assay, which uses L929-8, a newly isolated subclone of the murine fibroblastoid cell line L929, detects human TNF-alpha approximately 180-fold more sensitively than previously described L929 subclone assays. Maximum sensitivity is obtained by preincubating L929-8 cells at 37 degrees C with 2 micrograms/ml actinomycin D (1-2 h), then culturing with TNF at 40 degrees C for 20 h in medium containing high serum (15% FBS). Relative viable cell content in 96-well microtiter plates is determined colorimetrically by uptake of the non-carcinogenic dye neutral red. Other cytokines have no effect, either alone or in combination with TNF. Cytokines tested were IL-1 through IL-6, GM-CSF, G-CSF, CSF-1, LIF, TGF-beta, NGF, Epo or IFN-gamma, LPS, PGE2, dexamethasone and cyclosporin A, also have no effect, either alone or in combination with TNF. L929-8 cells maintain the above sensitivity to TNF for at least 4 months in continuous culture. Thus, the assay allows rapid, inexpensive, reliable and specific quantitation of rodent and human TNFs. Its very high sensitivity should allow accurate detection of biologically active TNF in biological fluids such as human serum.

Animals↗
PubMed1991

Brief intensive chemotherapy for metastatic non-small-cell lung cancer: a phase II study of the weekly CODE regimen.

Fifty-three patients, 17 with stage IIIB and 36 with stage IV non-small-cell lung cancer, were given CODE (cisplatin, vincristine, doxorubicin, and etoposide) plus antibiotic prophylaxis and an antiemetic regimen in an intensive chemotherapy program emphasizing weekly treatment and a planned brief duration (9-12 weeks); for 45 of these patients, the CODE program also included antifungal prophylaxis and supportive corticosteroids. Of the total study population, 33 patients (62%) responded to treatment, including five (9%) with complete response. The median survival for the entire group was 42 weeks (55 weeks for those with stage IIIB and 39 weeks for those with stage IV). More than 40% were alive at 1 year. Comparison of granulocyte counts of patients receiving prednisone with those of the subgroup to whom no corticosteroids were given showed less granulocytopenia for those receiving prednisone. Use of prednisone thus allowed improved delivery of myelosuppressive drugs. CODE was halted in nine patients because of disease progression. Although more constitutional side effects are associated with weekly chemotherapy than with standard chemotherapy, only 12 of the remaining 44 patients (27%) failed to receive at least 9 weeks of treatment. Serious toxicity was uncommon: There were no treatment-related deaths and only three episodes of neutropenia with fever. CODE is a novel treatment for non-small-cell lung cancer that this pilot study provided entirely in an outpatient setting over a 9-12 week period with an acceptable incidence of toxicity and a promising level of efficacy. Additional testing and comparison with other regimens or supportive care alone are warranted.

Adenocarcinoma↗
PubMed1991

Increased response of erythroid progenitors to interleukin-3 in sickle cell anemia: CFU-E-like behavior of circulating erythroid progenitors in liquid culture.

Erythroid progenitors circulating in peripheral blood and their response to erythropoietin (EPO), interleukin-3 (IL3), and phytohemagglutinin-stimulated, lymphocyte-conditioned medium (PHALCM) were assessed in sickle cell anemia (SCA) patients and controls. SCA patients have significantly higher numbers of circulating burst-forming unit-erythroid (BFU-E) compared with controls (mean +/- SEM, 940.27 +/- 129.11 per ml and 86.56 +/- 19.74 per ml, respectively; P less than 0.0001). At low doses of EPO, BFU-E-derived colonies were significantly increased in SCA patients compared with controls (each P less than 0.05). The EPO dose required to produce 50% of maximum colony numbers was 47 times greater in control subjects than in SCA patients. Moreover, in 11 of 17 patients with SCA, spontaneous BFU-E-derived colonies were formed without added erythropoietin. This phenomenon was not observed in control subjects (P = 0.035). PHALCM developed from mononuclear cells of SCA patients had significantly greater stimulatory effect than did that derived from controls regardless of the source of target cells (each P less than 0.05). A two-step study of IL3 sensitivity of erythroid progenitors was conducted. First, in a liquid culture system, circulating erythroid progenitors of SCA patients and controls were incubated in the presence of varying doses of IL3. During a second step, CFU-E-like colonies were observed in methylcellulose cultures of these cells. The mean numbers of colony-forming unit-erythroid (CFU-E)-like colonies was significantly higher in SCA patients compared with control subjects at low doses of IL3 (each P less than 0.02). The increased response of erythroid progenitors to IL3 and the increased production of hemopoietic growth factors (IL3 or non-IL3) contribute to the hemopoietic response in SCA patients. These mechanisms and increased sensitivity of the BFU-E to EPO may explain lower than expected EPO levels in SCA patients.

Anemia, Sickle Cell↗
PubMed1991

"Near miss" death in obstructive sleep apnea: a critical care syndrome.

OBJECTIVE: The objective of this study was to alert critical care physicians to the syndrome of obstructive sleep apnea with respiratory failure ("near miss" death) and to elucidate characteristics that might allow earlier recognition and treatment of such patients. DESIGN: We examined clinical and laboratory characteristics of eight patients with obstructive sleep apnea presenting to the ICU with respiratory failure. These characteristics were compared with those of eight stable apnea patients of similar severity but without a history of presentation with respiratory failure. SETTING: Medical ICU and pulmonary outpatient clinic at the Houston Veterans Administration Medical Center, a teaching hospital affiliated with Baylor College of Medicine. PATIENTS: Eight patients with obstructive sleep apnea who presented in, or developed, acute respiratory failure requiring tracheal intubation and mechanical ventilation were matched to eight stable obstructive sleep apnea outpatients from the chest clinic. MEASUREMENTS AND MAIN RESULTS: The records of these 16 patients were reviewed and multiple characteristics that might predict these obstructive sleep apnea patients prone to respiratory failure and death (called the "near miss" death group; n = 8) were examined. The mean age of the near miss group was 57 yrs. All eight patients presented with respiratory acidosis (mean pH 7.22), hypercarbia (mean PaCO2 82 torr [10.9 kPa]), and hypoxemia (mean PaO2 45 torr [6.0 kPa]). Six of the eight patients had concomitant chronic obstructive pulmonary disease as determined by clinical characteristics and spirometry. Predisposing factors included facial trauma, lower respiratory tract infections or bronchospasm, and use of pain medication. All but one of the near miss subjects had awake hypercarbia (mean PaCO2 49 torr [6.5 kPa]) and hypoxemia (mean PaO2 58 torr [7.7 kPa]) during periods of clinical stability while only two controls had concomitant chronic obstructive pulmonary disease and none had hypercarbia. The prevalence of a history of wheezing and prior hospitalization for "respiratory problems" were greater in the near miss group. Once cured of apnea, no patient presented with recurrence of respiratory failure in follow-up ranging from 6 to 80 months, and cor pulmonale recurred in only one patient during subsequent onset of central apneas. CONCLUSION: Patients with obstructive sleep apnea who have concomitant chronic obstructive pulmonary disease or hypercarbia and hypoxemia are more prone to develop severe respiratory failure and probable death than those patients with apnea alone. The current study shows that recurrent respiratory failure and presumably mortality from this acute complication can be reversed with effective treatment of the obstructive apnea.

Acute Disease↗
PubMed1991

Penile cancer--the sentinel lymph node controversy.

The management of lymph nodes in penile cancer has always been a problem. Sentinel lymph node biopsy was supposed to solve this problem but has not been universally accepted due to conflicting results. We herein present a case of penile cancer with bilateral pathologically positive inguinal lymph nodes associated with concurrent negative sentinel lymph node biopsies. We discuss the possible reasons for this situation and suggest guidelines to study this issue.

Biopsy↗
PubMed1991

Intensive weekly chemotherapy for the treatment of extensive-stage small-cell lung cancer.

The regimen of cisplatin, vincristine, doxorubicin, and etoposide (CODE) was designed to double the dose intensity of these drugs in comparison with a standard regimen (alternating cyclophosphamide, doxorubicin, and vincristine [CAV] and etoposide-cisplatin [EP]) for extensive-stage small-cell lung cancer (SCLC). The dose intensity was increased by more frequent treatments rather than by increasing the dose size. The structure of this outpatient protocol includes weekly administration of chemotherapy, alternation of myelosuppressive and nonmyelosuppressive treatments, supportive corticosteroids, gastroprotective agents, and prophylactic antibiotics. Although the duration of chemotherapy was brief (9 to 12 weeks), the total cumulative doses of drugs delivered were similar to the standard regimen. Patients with no residual disease outside the chest after chemotherapy received thoracic irradiation, and patients with complete responses (CRs) received prophylactic cranial irradiation. Eligible extensive-stage SCLC patients were ambulatory, younger than 66 years of age, and free of brain metastasis. Forty-eight extensive-stage SCLC patients were treated. Forty-five (94%) responded to chemotherapy, with 19 (40%) attaining CR. After consolidative thoracic irradiation, the CR rate was 56%. The median time to progression was 43 weeks, and the median survival was 61 weeks. The 2-year survival rate was 30%. The most common site of first relapse was brain (38%). Although two patients (4%) died of toxicity, overall toxicity was acceptable for an outpatient regimen. We conclude that the CODE regimen reliably produces palliative remissions for selected extensive-stage SCLC patients, and it may be associated with durable remissions for some patients. The results of this pilot study are sufficiently promising to justify a phase III trial of CODE versus standard (alternating CAV and EP) chemotherapy.

Adult↗
PubMed1991

Postcoital asthma and rhinitis.

Sexual intercourse as a trigger factor for attacks of asthma and/or rhinitis and the morbidity caused thereof is not well recognized. We present four patients (three males and one female) with postcoital asthma and/or rhinitis. Acute severe asthma subsequent to sexual intercourse in one male patient had resulted in several emergency department visits and hospitalization on one occasion. Anxiety was a predominant feature in the patients and their spouses that had interfered with their sexual life and worsened their disease. Late asthmatic response, on occasions, occurred in two patients. None of the patients developed wheezing dyspnea or rhinitis, nor did they have a fall in peak expiratory flow rates on climbing two flights of stairs, an exercise considered equivalent to energy expended during sexual intercourse. Thus, sexual excitement rather than exercise appeared to be the cause of postcoital asthma and rhinitis. Adequate pharmacotherapy along with counseling of the patients and their spouses restored normal sexual function and control of asthma and rhinitis. Postcoital asthma and rhinitis can easily be overlooked due to patient embarrassment and lack of physician awareness.

Adult↗
PubMed1991

Topical nasal anesthesia for flexible bronchoscopy. A comparison of four methods in normal subjects and in patients undergoing transnasal bronchoscopy.

We evaluated nasal anesthesia regimens by comparing, in seven normal men, four drug regimens: 1) 1 percent phenylephrine; 2) 4 percent lidocaine; 3) 1 percent phenylephrine + 4 percent lidocaine; and 4) 5 percent cocaine. After spraying each drug into the anterior nares, vasoconstriction, decongestion, and nasal anesthesia (measured as transnasal depth of nasogastric (NG) tube insertion before discomfort) were assessed. There were no significant differences in NG tube insertion depth between the regimens (p = 0.54). Insertion depth was significantly increased after 10 ml of 2 percent viscous lidocaine were sniffed (p less than 0.004), but again, differences between regimens were not significant (p = 0.051). One hundred bronchoscoped patients received one of the following sprayed into the nose: 1) placebo (P); 2) 1 percent phenylephrine + P; 3) 1 percent phenylephrine + 4 percent lidocaine; or 4) 5 percent cocaine + P. Each patient then sniffed viscous lidocaine. There were no significant differences between regimens for any of the following: 1) nasal resistance to bronchoscope insertion, 2) patient's nasal discomfort, or 3) bronchoscopist's perception of patient discomfort. We conclude that sprayed anesthetics contribute little to nasal anesthesia and any regimen appears acceptable when viscous lidocaine is used.

Administration, Intranasal↗
PubMed1991

Imaging of vascular complications associated with renal transplants.

Vascular complications associated with renal transplants are a significant cause of graft dysfunction. The most common complications are arterial and venous stenoses and thromboses and intrarenal and extrarenal arteriovenous fistulas and pseudoaneurysms. Although angiography is the imaging gold standard for the diagnosis of these disorders, Doppler sonography, scintigraphy, and occasionally CT are capable of detecting them. An awareness of the different imaging appearances of each complication will aid in their early detection and treatment. In this review, we present this information and provide a perspective on the relative roles of these techniques in the detection of vascular complications from renal transplants.

Diagnostic Imaging↗
PubMed1991

Electrochemiluminescence detection for development of immunoassays and DNA probe assays for clinical diagnostics.

Electrochemiluminescence (ECL) has been developed as a highly sensitive process in which reactive species are generated from stable precursors (i.e., the ECL-active label) at the surface of an electrode. This new technology has many distinct advantages over other detection systems: no radioisotopes are used; detection limits for label are extremely low (200 fmol/L); the dynamic range for label quantification extends over six orders of magnitude; the labels are extremely stable compared with those of most other chemiluminescent systems; the labels, small molecules (approximately 1000 Da), can be used to label haptens or large molecules, and multiple labels can be coupled to proteins or oligonucleotides without affecting immunoreactivity, solubility, or ability to hybridize; because the chemiluminescence is initiated electrochemically, selectivity of bound and unbound fractions can be based on the ability of labeled species to access the electrode surface, so that both separation and nonseparation assays can be set up; and measurement is simple and rapid, requiring only a few seconds. We illustrate ECL in nonseparation immunoassays for digoxin and thyrotropin and in separation immunoassays for carcinoembryonic antigen and alpha-fetoprotein. The application of ECL for detection of polymerase chain reaction products is described and exemplified by quantifying the HIV1 gag gene.

2,2'-Dipyridyl↗
PubMed1991

Cerebrospinal dehydrogenases in central nervous system infections.

Cerebrospinal fluid (CSF) dehydrogenases were studied in 42 controls, 23 children with pyogenic meningitis, 22 with tuberculous meningitis and 19 with encephalitis to assess their usefulness in differentiating between the different central nervous system infections. CSF-LDH and ICD activity was increased in CNS infections (p less than 0.0001), LDH being significantly higher (p less than 0.001) in pyogenic meningitis than in tuberculous meningitis or encephalitis. However, ICD activity was significantly different in each of these conditions (p less than 0.001). The dehydrogenase activity declined with subsequent clinical improvement, in all children with meningitis. A significant direct relationship was found between the enzyme activity and CSF protein content as well as total cell count. The 95% confidence interval confirms the utility of assaying CSF dehydrogenase activity to differentiate various CNS infections, thus improving the diagnostic ability.

Acute Disease↗
PubMed1991

Morphometric studies of normal muscle mitochondria.

The study describes mitochondrial morphometry in normal adult limb muscles of various mammalian species. The size, area, shape, and volume of mitochondria were compared in two regions (subsarcolemmal and intermyofibrillary) and fiber types (type 1 and type 2) of the 1) human and monkey quadriceps, 2) cat soleus and caudofemoralis-CF, and 3) rat soleus and extensor digitorum longus-EDL. The Z band width showed distinct differences between the two types of fibers in all muscles. The mitochondrial size and volume varied in different muscles but the shape remained oval throughout. The human quadriceps mitochondria were the smallest in size and volume. The monkey and rat muscles showed higher mitochondrial volume which was not significantly different between the two fiber types. The cat soleus and EDL muscles showed significant difference in the mitochondrial volume of two fiber types and also significant correlation between the Z band width and the mitochondrial volume, the soleus being pure type 1 fibers and the EDL being pure type 2B fibers. We conclude that only the shape of mitochondria, but not the size and volume, is independent of the species, the type of muscle and the region of a fiber.

Animals↗